Members of modern industrial societies have embraced today's advanced electronic consumer products so enthusiastically that people who are excluded from the use of such products have become, in a sense, excluded from the society's mainstream. Unfortunately, many of these products are difficult to operate. The video cassette recorder (VCR), for example, is often cited as the epitome of such a product, as it provides a highly desirable service but presents such a difficult operational interface that even fully capable adults are sometimes challenged by its intricacies. Cellular telephones fit this same general category.
The operation of modern cellular telephones over their full range of possibilities is inherently difficult because advanced users demand a complex collection of options and features. The problems of complexity are compounded by the problems of ergonomics that come with miniaturization--cellular telephones must be small in order to be readily portable, and therefore must have small keypads and tightly constrained visual displays.
Even the basic operation of dialing a cellular telephone is complex in its own right. First, the user typically enters a four-digit password, whose purpose is to unlock the phone's security apparatus designed to thwart unauthorized users. Next, the user enters the called-party telephone number digit-by-digit. Finally, the user enters a send command, which instructs the phone to forward the telephone number to a cellular base station. Not only is the traditional cellular telephone dialing process complex, it violates a pattern long established and well ingrained for dialing a wireline telephone.
As an alternate to the traditional cellular telephone dialing process, many cellular phones provide speed dialing. To set the stage for speed dialing, the user preloads a set of frequently dialed telephone numbers into the phone's nonvolatile memory. Each speed-dial number is paired with an integer. To dial one of the preloaded numbers. the user first unlocks the phone by entering a password through its keypad, and then enters a recall or memory command followed by the integer paired with the desired number. In order to take advantage of this option, however, the user must remember the correct pairing of integers and telephone numbers, or must access this association through keystrokes guided by a menu comprising cryptic visual display messages, and must, of course, remember the password and understand the required sequence of keypad operations. So although the speed-dial mode may require the user to enter fewer keystrokes than the conventional dialing mode, the speed-dial mode is arguably more demanding cognitively.
In any case, the complexities of dialing a cellular phone are troublesome to a significant population of would-be users. Children, for example, are often unable to dial properly, as are adults who suffer from Alzheimer's disease or other cognitive impairment, or who are unable to engage the keypad or display because of physical limitations such as diminished dexterity or sight. Because of the complexity of dialing, people whose lives might well be significantly improved by having convenient access to a cellular telephone are effectively deprived of the cellular telephone's benefits.
In response to these concerns, special-purpose phones have been proposed that have the capability to dial only a limited set of prestored telephone numbers by way of a few oversized keys or buttons that replace the phone's conventional keypad, or through special keys appended to a standard telephone in addition to the standard keypad. Such phones, however, suffer the drawbacks as well as the advantages of being special-purpose. Simply put, special-purpose phones are relatively expensive as compared to conventional phones because they are not mass-market products and therefore cannot provide mass-market economy of scale. Consequently, the target population remains substantially excluded from the benefits of cellular telephone service for reasons of cost rather than ergonomics. Although in some circumstances a mass-market cellular telephone could be dialed or its password entered by a child's baby-sitter or an adult's caretaker, this approach is often completely unsatisfactory, as leaving the phone unprotected by the password and fully operational opens the risk that calls will be placed and charges incurred by unauthorized users.
Thus, a need remains to equip mass-market wireless telephones such as cellular telephones with a simplified dialing mode that retains the advantages of password protection, so that these phones can be conveniently and economically used by children, victims of Alzheimer's disease, the cognitively impaired, the partially sighted, and those whose fingers are unable to navigate the small keypad of today's products. This need is expected to become increasingly urgent in view of evident trends toward ever-smaller and ever-more-complex cellular telephones.